It's time to open a Perijove-8 thread. Only a little more than two days are left for voting. For this perijove pass, JunoCam is scheduled to use more memory than during any previous perijove pass. Therefore, we have the best conditions to collect a considerable number of images, and images of good quality.

One of my votes went to an image near the equator, in order to give the ops team the opportunity to take a lossless image from very close up. In previous perijoves, these very close ups suffered a bit from lossy compression. This time, we may have one of the rare chances to find out, whether subtle small features are present, but escaped notice due to high compression rates.My other votes are for the subpolar regions with the fascinating FFRs.But I don't make specific recommendations, since I'm hoping for a full latitude coverage in good quality. Besides their science value, such a sequence will be a good basis for a pole to pole animation.

I'm also curious, whether we can learn more about the polar regions. These images are scheduled in any case.Besides low TDI images, I'm hoping for some high TDI images in order to get high S/N for the circumpolar storm systems.

For Perijove-8, we'll get approach and departure images for a global map. So close to solar conjunction, those are of more interest than in times with good observational conditions from Earth. Unfortunately, during Perijove-9, obtaining a global map will be much harder, if possible at all.

And as a special bonus, an image if Io is scheduled for PJ-08.

My time for processing these images is very restricted in September. But I'll try to cover the full suite of close-ups as soon as the raws become available, nevertheless.

Juno's orbit around Jupiter is evolving. This is the last full opportunity to image Jupiter from 5 days out to 5 days after perijove. We will want to take advantage of this last chance for continuity at every latitude.

Pretty sure that they wouldn't announce EOM like that anyhow.

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A few will take this knowledge and use this power of a dream realized as a force for change, an impetus for further discovery to make less ancient dreams real.

This may have something to do with the fact that the JunoCam specs call for it to survive only the first eight orbits. Everything beyond that is a bonus.

Sorry for the confusion! This will be the last time we select Points of Interest to image based on a public vote. In the near term (PJ9 and PJ10) it is because Jupiter is too close to the sun for earth-based observers to see it, and we won't be able to acquire a marble movie because of the orientation of Juno's orbit. After PJ10 the orbit has moved around such that the geometry will be less intuitive and thus voting would be more complicated. At this moment we are discussing how to replace voting with something else. But we will continue imaging!!

Sorry for the confusion! This will be the last time we select Points of Interest to image based on a public vote. In the near term (PJ9 and PJ10) it is because Jupiter is too close to the sun for earth-based observers to see it, and we won't be able to acquire a marble movie because of the orientation of Juno's orbit. After PJ10 the orbit has moved around such that the geometry will be less intuitive and thus voting would be more complicated. At this moment we are discussing how to replace voting with something else. But we will continue imaging!!

Will there be any distant moon encounters in upcoming orbits? I remember your earlier piece about that, but it was based on the planned orbit.

For the small team, there is currently a very high work load with preparing the command sequence for PJ-08, defining a possible extension for the missionjuno website, and preparing talks for EPSC2017. During PJ-08, Io will be imaged.I guess, that next week, someone might have time to look up distant moon encounters during future orbits.

There's a distant moon encounter on every orbit, for suitable definition of "distant". Or were you talking about the outer non-galilean moons?

A quick non-official survey to early 2021 shows closest approaches of 172K km to Io, 146K to Europa, 109K to Ganymede, and 678K to Callisto. None of these are close enough to be especially wonderful IMHO.

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Disclaimer: This post is based on public information only. Any opinions are my own.

After PJ10 the orbit has moved around such that the geometry will be less intuitive and thus voting would be more complicated.

To expand on this a little, remember that Juno is solar-powered and so its solar panels must always face the sun (approximately), and Junocam is pointed 90 degrees away from the sun line. In the original mission plan, the orbit was roughly over the terminator over the entire course of the mission, so Junocam was pointed at the planet for part of every spin. Now that the mission is going to last so much longer, Jupiter moves around the sun much more, and the orbit (which is fixed in inertial space, more or less) drifts away from the terminator. If you consider the case when the orbit is 90 degrees from the terminator, Junocam never sees the planet at all for much of a perijove pass.

All of this is complicated by the slightly different orientations that are used (Earth-pointing, normal to the orbit plane, etc.) And Juno can go off-sun and run on batteries for a while, and this will likely be done for some orbits. But all of these scenarios are much more complex than what the public targeting software was designed to handle, so we are still evaluating what we can do within the constraints. Only partly in jest, I suggested at one point that we let the public figure out what might be visible from the available SPICE kernels and then let them vote on that.

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Disclaimer: This post is based on public information only. Any opinions are my own.

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